package huawei0814;

import java.util.Scanner;

public class LongestSubsequence {
    public static void main(String[] args) {
        Scanner scanner=new Scanner(System.in);
        while (scanner.hasNext()){
            int n=scanner.nextInt();
            int[] nums1=new int[n];
            int[] nums2=new int[n];
            for (int i = 0; i <n ; i++) {
                nums1[i]=scanner.nextInt();
            }
            for (int i = 0; i <n ; i++) {
                nums2[i]=scanner.nextInt();
            }
            System.out.println(n-lengthOfLCS(nums1,nums2));
        }
    }
    public static int lengthOfLCS(int[] nums1, int[] nums2) {
        int n1 = nums1.length, n2 = nums2.length;
        int[][] dp = new int[n1 + 1][n2 + 1];
        for (int i = 1; i <= n1; i++) {
            for (int j = 1; j <= n2; j++) {
                if (nums1[i - 1] == nums2[j - 1]) {
                    dp[i][j] = dp[i - 1][j - 1] + 1;
                } else {
                    dp[i][j] = Math.max(dp[i - 1][j], dp[i][j - 1]);
                }
            }
        }
        return dp[n1][n2];
    }
}